Touch sensitive devices are becoming increasingly common. Examples include the iPad®, iPhone®, various tablet devices, mobile devices running the Google® Android® operating system, Symbian-based devices, Nokia mobile devices, and many more. Some of these devices use virtual keyboards in which a keyboard is displayed on the touch sensitive display to facilitate text entry. In the case of any iPhone® a “ABC” button and a “123” button are provided which have the effect of changing the displayed virtual keyboard between one showing the alphabet and one showing the numbers and symbols.
There are various devices which display additional buttons on the display alongside a keyboard. For example, US2009/0077464 (Goldsmith) describes a touch sensitive device in which a list of candidate words are presented on an interface to correct text input from a user. US2008/0046496 (Kater) describes a touch sensitive device having a touch screen with a key zone which comprises a main key area, number key area, and a function key area. EP2068236A1 (Sony) describes a graphical user interface on a smart phone which displays a plurality of icons. U.S. Pat. No. 7,249,325 (Donaldson) describes a graphical user interface having a tab display area with the tabs being indexed by alphabets and optionally arranged as a circular array.
Despite these known devices, there is a problem in displaying extended or modifier keys on such virtual keyboards of devices, in particular because of space limitations. There are potentially many such keys which might be needed including function keys, cursor keys (arrows), keys with special functions such as Control, Alt, Insert, Delete, Escape, as well as operating systems specific keys such as the “Apple” and “Windows” keys found on desktop keyboards. There is a need for improved user interfaces which make it easy for a user access such keys, in particular on the limited real estate of a mobile device touch screen.